Machine for milling the valve-ports of engines



2 Sheets-Sheet 1. w

(No Model.)

J. DAVIS. I

MACHINE FOR MILLING THE VALVE PORTS OF ENGINES. No. 414.756.

Patented Nov. 12,; 1889.

myEm'oR,

Atty.

N. PETERS. Phulol-illlognphur, Wnhinginn. D. C.

(NoiModeL) 2 Sheets-Sheet 2.

V J. DAVIS. I MACHINE FOR MILLING THE VALVE PORTS 0F ENGINES. No. 414,756. Patented Nov. 12, 1889.

l A 6 W WITNEQESS N, PEYERS, Phelo-Lilhcgraphar, Wunhingtnn. U C.

UNITED STATES PATENT, OFFICE.

JOSEPH DAVIS, or ALTOONA, PENNSYLVANIA.

MACHINE FOR MILLING THE VALVE-PORTS OF ENGINES.

SPECIFICATION forming part of Letters Patent No. 414,756, dated November 12, 1889.

Application filed August 26, 1889. Serial No. 321,942. (No model.)

' idly and accurately finished or cut out to the form, dimensions, and relative location required; to which end my invention, generally stated, consists in the combination of a supporting-frame adapted to be temporarily fixed upon an engine-cylinder, two carriages fitted to traverse at right angles one to the other in said frame, a cutter-shaft journaled in one of said carriages, and a series of milling-cutters and adjusting-blocks fixed upon said shaft:

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings, Figure 1 is a side view in elevation of a machine for finishing valve-face ports embodying myinven-v tion, the same being shown as adjusted in position for operation upon a locomotive-cylinder; and Figs. 2 and 3 are vertical central sections, on an enlarged scale, through the same, taken at right angles one to the other.

My improvement is specially designed for and is herein shown as applied in finishing the steam and exhaust ports I) b and c of the valve-face a of a locomotive-cylinder A, the construction of which accords with the present American standard.

In the practice of my invention I provide a supporting-frame 1, which is substantially of rectangular form, and is provided with lateral lugs 2 for the reception of bolts 3, by which it is secured during operation to the cylinder whose ports are to be subjected to its action, the bolts 3 engaging at their lower ends threaded holes, which are, as heretofore, formed in the cylinder for the reception of a corresponding number of steam-chest bolts, and their upper ends being threaded to receive nuts 1, by which the supporting-frame is clamped firmly against the cylinder-face 1.

A vertical feed-screw 5, journaled in a central bearing 6, formed in a transverse bar 7 on the top of the frame 1, and provided with a hand-wheel 8 and with collars to prevent longitudinal movement, engages a nut 9 in a carriage 10, which is fitted to slide vertically between suitable guide-faces 11 on the sides of the frame 1. Lateral dovetailed guides 12, formed on the bottom of the carriage 10, engage corresponding lateral slides 13 on the top of a carriage 14, which is thereby supported and adapted to slide on the carriage 10 in line with the ports 1) c I), which are to be cut. Wear or lost motion between the guides 12 and slide 13 may be taken up by an interposed gib or liner 15, provided with suitable adjusting-screws.

Movement is imparted to the carriage 14, in the direction of the length of the ports be b, by a horizontal feed-screw 16, provided with a hand-Wheel 17, and journaled in a bearing 18 on the bottom of and in the vertical central plane of the carriage 10, said screw having collars to prevent longitudinal movement, and engaging a nut 19, which is secured in the same plane upon the top of the carriage 14.

A cutter-shaft 20 is journaled at right angles to the feed-screw 16 in bearings 21, which project downwardly from the carriage 14 at each side thereof, and are provided with removable caps 22, and a series of rotary milling-cutters. 23, each adapted to face off one side of a port, is secured removably and adjustably upon the cutter-shaft 20. The cutters 23 are held in position circumferentially upon the shaft by a key 24, upon which they are adaptedto slide longitudinally, their relative position thereon being adjusted in accord-ance with the required width of the finished ports and bridges by a series of interposed distancepieces or adjusting-blocks 25 of suitable thickness, which are likewise fitted upon the key 24:. The series of cutters and adjusting-blocks is clamped in position longitudinally on the shaft 20, between a shoulder 26, fixed thereon, and a nut 27, engaging a screw-thread 28 on the shaft at the opposite end of the series. It will be obvious that when longitudinal adj ustment of the cutters is not deemed essential, lateral hubs formed upon the cutters and maintaining the cutting-faces thereof at a determined distance apart may be substituted for and would constitute a mechanical equivalent of the separate adjustingblocks described and shown. The shaft 20 is held in position longitudinally in its bearings and its longitudinal adjustment therein admitted of as required by a nut 29, engaging a thread 30 on the shaft and abutting against one of its bear- 1o ings 21, and a set-screw 31, engaging a nut 32, fixed to the outside of the opposite hearing and abutting against the adjacent end of the shaft. Rotation is imparted to the cutter-shaft 20 by a belt from a suitable prime mover or counter-shat't, motion being preferably, as shown, transmitted to the cut- 'ter-shaft through the intermediation of a drivingshaft 34, carrying upon one end a pulley. 35, which receives the driving-belt 33, and upon the other a spur-pinion 36, which meshes with a corresponding gear 37, fixed on the cutter-shaft.

My improvement enables absolute accuracy of the rectilineal form and relative position of the ports to be attained, with a material reduction of time as compared with the ordinary manipulation, and the cutters being once adjusted for any standard cylinder uniformity of finish is insured in the entire series of such standard upon which it may be employed, such uniformity being specially important under the present general requirement of interchangeability of parts in elements relating to the stcamdistribution mem- 3 5 bers of locomotive or other engines.

The machine is of such comparatively small weight and dimensions as to be readily moved from one cylinder to another, and its attachment and detachment can be quickly effected even by unskilled workmen.

I claim as my invention and desire to secure by Letters Patent-- I. In a machine for finishing valve-face ports, the combination of a supporting-frame,

two carriages fitted to traverse at right angles one to the other therein, a cutter-shaft journaled in one of said carriages, and a series of milling-cutters fixed upon said shaft, substantially as set forth.

2. In a machine for finishing valve-face ports, the combination of asupporting-framc, two carriages fitted to traverse at right angles one to the other therein, a cutter-shaft journaled in one of said carriages, and a series of alternately-located milling-cutters and adjusting-blocks fixed upon said shaft,snbstantially as set forth.

In a machine for finishing valve-face ports, the combination of a supporting-frame, a series of lateral clam ping-bolts fittin g therein and adapted to engage steam-chest boltholes, an upper carriage fitted to slide vertically in guides in the frame, a downward feed-screw journaled and held against longitudinal movement in a bearing in the frame and engaging a nut on said carriage, a lower carriage fitted to slide horizontally in guides on the upper carriage, a longitudinal feedscrew journaled and held against longitudinal movement in a bearing in the upper carriage and engaging a nut on the lower carriage, a cuttershaft journaled in hearings on the lower carriage transversely to the longitudinal feed-screw, and a series of millingcutters fixed upon said shaft, substantially as set forth.

4. In a machine for finishing valve-face ports, the combination of a supporting-frame adapted to be temporarily fixed upon an engine-cylinder, an upper and a lower carriage fitted to traverse at right angles, one to the other, in said frame, feed-screws actuating said carriages, a cutter-shaft journaled in the lower carriage, a series "of milling-cutters fixed upon said shaft, a shaft carrying a d riving-pnlley and journaled in the lower carriage, and gearing connecting said shaft with the cutter-shaft, substantially as set forth.

JOSEPH DAVIS.

Witnesses:

W. l). CoUcH, JAMES MORGAN. 

